Arguing with Lin Fan about regression to the means
Posted: Sun Sep 21, 2014 5:04 pm
I've practically given up on explaining what regression in basketball means to him. He constantly insists the term means deterioration, and that Lin didn't deteriorate because his 3pt percentage improved. What he didn't understand was that Lin's 3pt volume was very low last year, so any small number of increments would move the percentage up. The difference between the year before last season, and this season's was minute if you look at the hard number.
His 3P M and A were 1.1-3.1 in 2013 and 1.2-3.2 in 2014. He went from .339 to .358. Using percentage alone to grade his improvement was dishonest. His shots from the two years listed were basically identical in averages. They don't have to be exactly alike when you're talking about averages.
The main why I use regression to describe his play last year though is that he had a rubber band effect. He went from starting out really hot, something about 50%< on his 3 pt in the first 8 games. After that he dropped to a low of almost 20%. In the end, it all equaled out to his average from the year before in Houston.
Yet he insists that Lin improved, I've backtracked on my meaning of regression and that regression means deterioration. He doesn't understand that regression to means isn't regression downwards but towards the average whether that is up or down.
If anyone's interested, they can take a look at the argument below under the topic Jilliebeans (me) I wish Jeremy would just improve his game instead of making funny videos all the time. I want to take him a little more seriously at this point.
The argument starts at Michael Jenkins, when he asked, "If he regressed, why did he have a career-year in 3-point percentage?"
https://www.youtube.com/watch?v=SNBIVUeMrvU
I'm Lin fan, but I believe objectivity is most important when discussing basketball.
His 3P M and A were 1.1-3.1 in 2013 and 1.2-3.2 in 2014. He went from .339 to .358. Using percentage alone to grade his improvement was dishonest. His shots from the two years listed were basically identical in averages. They don't have to be exactly alike when you're talking about averages.
The main why I use regression to describe his play last year though is that he had a rubber band effect. He went from starting out really hot, something about 50%< on his 3 pt in the first 8 games. After that he dropped to a low of almost 20%. In the end, it all equaled out to his average from the year before in Houston.
Yet he insists that Lin improved, I've backtracked on my meaning of regression and that regression means deterioration. He doesn't understand that regression to means isn't regression downwards but towards the average whether that is up or down.
If anyone's interested, they can take a look at the argument below under the topic Jilliebeans (me) I wish Jeremy would just improve his game instead of making funny videos all the time. I want to take him a little more seriously at this point.
The argument starts at Michael Jenkins, when he asked, "If he regressed, why did he have a career-year in 3-point percentage?"
https://www.youtube.com/watch?v=SNBIVUeMrvU
I'm Lin fan, but I believe objectivity is most important when discussing basketball.